I am unable to save an AVFoundation video to a local url

I'm a new to programming and Objective-C (~6 weeks) and now I'm working with AVFoundation for the first time. My goal is a stretch for my level, but shouldn't be too difficult for someone familiar with the framework.

My goal is to create a 'Snapchat' style custom camera interface that captures a still image when you tap on the button, and records video when you hold it down.

I've been able to piece together and crush through most of the code (video preview, capturing still images, programmatic buttons, etc.), but I'm not able to successfully save the video locally (will add it to a project built on top of Parse later this week).

The way I've constructed my code is I initialize the session in the first set of methods, and then break apart image and video capture into their own separate sections. The input device is AVMediaTypeVideo and it outputs to AVCaptureStillImageOutput and AVCaptureMovieFileOutput respectively.

If you want to use AVCaptureMovieFileOutput to record videos, you cannot set the AVCaptureSession's sessionPreset to AVCaptureSessionPresetPhoto, that's for still images only. For high quality video output I would recommend using AVCaptureSessionPresetHigh.